This invention concerns keyless automobile lock and ignition systems (often referred to as smart key) in which the presence of a key fob is electronically detected by means of a radio pulse transponder in the key fob and antennas in the car body. In these systems, the car is unlocked automatically when the handle is operated or a button pushed. Locking is accomplished in a similar way or by simply walking away.
The ignition switch is also operated without the need to insert a key into the ignition switch lock by the same wireless detection of the presence of the key fob in the passenger compartment. The system neutralizes the electronic immobilizer usually now included in automobile electronics and allows starting the car by simply pushing a button or turning the ignition switch without the need to insert a key into the switch.
While very convenient, this system creates possibilities of security risks and also allows inconvenient situations to inadvertently arise.
For example, if after starting, the driver momentarily exits the car and somehow leaves the key fob somewhere before reentering the car, he or she can drive off, and then after reaching a destination cannot restart the car since the key fob is not present. A manual operation using the key is also not possible if the key is left with the fob.
While a warning message is displayed on the instrument panel in some designs, indicating that the key fob is not detected by the system, it is easy to not notice this displayed message which may be blocked by the steering wheel.
In another common situation which could be encountered, if a driver allows a valet attendant to drive off with the car, if the driver does not give the key fob to the attendant, the attendant will be unable to start the car when retrieving the car until after obtaining the key fob from the driver, slowing the return of the car to the driver.
Also, if the valet forgets to surrender the key fob to the owner, the owner can unknowingly drive away without the key fob and subsequently be unable to restart the car with the car (which usually is left running while the attendant gets out and the owner enters the car).
Security risks can also arise, as where a car is inadvertently left running (which can be very quiet and nearly undetectable in many cars) and with the doors unlocked, such that a thief can simply enter and drive off in the car.
With newer locking systems, it is easy for a driver to think the car has been locked when in fact the locking has not been accomplished.
Again, beep cues or visual displays can easily be missed, particularly when a driver is in a hurry.
It is also known to lock the transmission shift lever until the key fob is authenticated by the smart key controller system as described in U.S. 2009/0151412A1. However, once authentication has occurred in that system, the transmission shift lever can be freely operated such that the above problems are still encountered.
Accordingly, it is an object of the present invention to provide a keyless or smart key system of the type described which has a fail-safe feature that insures that the above described inconvenience or security risk situations are positively prevented without the need for particular attentiveness of the driver the location of the key fob on to related beep cues or displays.